Radiological and pathological assessment of hepatocellular carcinoma response to radiofrequency. A study on removed liver after transplantation

BACKGROUND

The real efficacy of radiofrequency ablation (RFA) in destroying hepatocellular carcinoma is not completely known, nor is the ability of computed tomography (CT) to precisely assess response. Our aims were to analyze pathological response, tumor size influence, and CT response evaluation.

MATERIALS AND METHODS

This was a retrospective study of 30 hepatocellular carcinoma nodules treated by RFA before liver transplant (LT) in 28 patients. Pathological study of the whole removed liver was then performed and the tumor response was classified as complete, incomplete, or absent. The biggest nodule diameter was estimated by CT or ultrasound. The procedure was carried out percutaneously in all but 3 patients, and in those 3 it was done surgically.

RESULTS

The pathological response was complete in 14 nodules (46.7%) and incomplete in 16 (53.3%). The differences in mean preoperative diameter between cases with complete and incomplete response were not significant (p = 0.3). We found that small tumors were not always completely destroyed, whereas bigger tumors could be successfully deleted. There was no clear association between any location and better or poorer response. The detection of RFA incomplete response by means of CT scan had 50% sensitivity and 100% specificity.

CONCLUSIONS

In our experience, RFA can achieve some degree of tumor destruction in every treated case of hepatocellular carcinoma, the complete response rate being slightly lower than half. We have not found any association of response with tumor size or interval RFA-transplant. Second, CT had not enough sensitivity to assess RFA response of hepatocellular carcinoma.